Silylating agents have been developed in the art which react with and coat surfaces, such as silica surfaces. For example, silylating agents for use in modifying silica used in high performance chromatography packings have been developed. Monofunctional silylating agents have been used to form monolayer surface coatings, while di- and tri-functional silylating agents have been used to form polymerized coatings on silica surfaces. Many silylating agents, however, produce coatings with undesirable properties including instability to hydrolysis and the inadequate ability to mask the silica surface which may contain residual acidic silanols.
Silylating agents have been developed for the silylation of solid substrates, such as glass substrates, that include functional groups that may be derivatized by further covalent reaction. The silylating agents have been immobilized on the surface of substrates, such as glass, and used to prepare high density immobilized oligonucleotide probe arrays. For example, N-(3-(triethoxysilyl)-propyl)-4-hydroxybutyramide (PCR Inc., Gainesville, Fla. and Gelest, Tullytown, Pa.) has been used to silylate a glass substrate prior to photochemical synthesis of arrays of oligonucleotides on the substrate, as described in McGall et al., J. Am. Chem. Soc., 119:5081–5090 (1997), the disclosure of which is incorporated herein by reference.
Hydroxyalkylsilyl compounds that have been used to prepare hydroxyalkylated substances, such as glass substrates. N,N-bis(hydroxyethyl)aminopropyl-triethoxysilane has been used to treat glass substrates to permit the synthesis of high-density oligonucleotide arrays. McGall et al., Proc. Natl. Acad. Sci., 93:13555–13560 (1996); and Pease et al., Proc. Natl. Acad. Sci., 91:5022–5026 (1994), the disclosures of which are incorporated herein. Acetoxypropyl-triethoxysilane has been used to treat glass substrates to prepare them for oligonucleotide array synthesis, as described in PCT WO 97/39151, the disclosure of which is incorporated herein. 3-Glycidoxy propyltrimethoxysilane has been used to treat a glass support to provide a linker for the synthesis of oligonucleotides. EP Patent Application No. 89 120696.3.
Methods have been developed in the art for stabilizing surface bonded silicon compounds. The use of sterically hindered silylating agents is described in Kirkland et al., Anal. Chem. 61: 2–11 (1989); and Schneider et al., Synthesis, 1027–1031 (1990). However, the use of these surface bonded silylating agents is disadvantageous, because they typically require very forcing conditions to achieve bonding to the glass, since their hindered nature makes them less reactive with the substrate.
It is an object of the invention to provide functionalized silicon compounds that are provided with derivatizable functional groups, that can be used to form functionalized coatings on materials, such as glass. It is a further object of the invention to provide functionalized silicon compounds that can be used to form coatings on materials that are stable under the conditions of use.